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991.
Location plays a major role in the building of artistic, technological or scientific movements that emerge in specific locations before achieving a worldwide reach. However, a deeper understanding is needed about the interplay of local/global knowledge dynamics in the epistemic construction of a movement. Based on an in-depth longitudinal study of a critical case, this article sheds light on these issues by analysing the case of ‘techno-emotional cuisine’, a global gastronomic movement initiated and led by chef Ferran Adrià and his team at the restaurant elBulli in Catalonia (in Northern Spain). The results suggest that the dynamics of formation of a new epistemic movement depend on the form and nature of the interactions between the local buzz and global pipelines, and on the capacity of the originating community to develop and diffuse the new rules and ‘episteme’ on a global scale while consolidating them locally. 相似文献
992.
Abstract When an extraordinary wave under inhibited reflection conditions is incident on an interface between a uniaxial crystal and an isotropic medium, the reflected extraordinary wave is evanescent and the polarization of the refracted wave changes from linear to elliptical. In the present paper it is shown that the refracted ray undergoes a shift which is not only longitudinal (as the Goos—Hänchen effect in total reflection in isotropic interfaces) but also transversal. The structure of the evanescent reflected wave is studied and the polarization of the transmitted wave is analysed. 相似文献
993.
Mohammad Mehrali Emad Sadeghinezhad Sara Tahan Latibari Mehdi Mehrali Hussein Togun M. N. M. Zubir S. N. Kazi Hendrik Simon Cornelis Metselaar 《Journal of Materials Science》2014,49(20):7156-7171
Nanofluids perform a crucial role in the development of newer technologies ideal for industrial purposes. In this study, Nitrogen-doped graphene (NDG) nanofluids, with varying concentrations of nanoparticles (0.01, 0.02, 0.04, and 0.06 wt%) were prepared using the two-step method in a 0.025 wt% Triton X-100 (as a surfactant) aqueous solution as a base. Stability, zeta potential, thermal conductivity, viscosity, specific heat, and electrical conductivity of nanofluids containing NDG particles were studied. The stability of the nanofluids was investigated by UV–vis over a time span of 6 months and concentrations remain relatively constant while the maximum relative concentration reduction was 20 %. The thermal conductivity of nanofluids was increased with the particle concentration and temperature, while the maximum enhancement was about 36.78 % for a nanoparticle loading of 0.06 wt%. These experimental results compared with some theoretical models including Maxwell and Nan’s models and observed a good agreement between Nan’s model and the experimental results. Study of the rheological properties of NDG nanofluids reveals that it followed the Newtonian behaviors, where viscosity decreased linearly with the rise of temperature. It has been observed that the specific heat of NDG nanofluid reduced gradually with the increase of concentration of nanoparticles and temperature. The electrical conductivity of the NDG nanofluids enhanced significantly due to the dispersion of NDG in the base fluid. This novel type of fluids demonstrates an outstanding potential for use as innovative heat transfer fluids in medium-temperature systems such as solar collectors. 相似文献
994.
Falk Heinroth Simon Münzer Armin Feldhoff Sven Passinger Wei Cheng Carsten Reinhardt Boris Chichkov Peter Behrens 《Journal of Materials Science》2009,44(24):6490-6497
In this work, the preparation of three-dimensional hierarchical pore structures by a combination of laser-based templates
and the self-organization process of mesostructured titania is presented. For this purpose macrostructured polymers produced
by two-photon polymerization act as a template for the deposition of a mesostructured titania film from a solution containing
an amphiphilic block copolymer by dip coating. A carefully applied calcination procedure removes both the macrotemplating
polymer and the mesotemplating surfactant molecules so that a replica of the initial polymer structure with a hierarchical
(macro- and meso-) pore system is obtained. In addition, the titania, which is amorphous after deposition, is transferred
into crystalline anatase during calcination. Materials with dual pore systems are interesting for possible applications in
catalysis and sorption, and three-dimensional crystalline structures from materials with high refraction index are attractive
for photonic applications, for example as photonic crystals. 相似文献
995.
One driver skill that has been found to correlate with crash risk is hazard perception ability. The purpose of this study was to investigate how hazard perception latencies change between high and low sleepiness for a high risk group (novice drivers) and a lower risk group (experienced drivers). Thirty-two novice drivers (aged 17-24 years) and 30 experienced drivers (aged 28-36) completed a validated video-based hazard perception test, in which participants were asked to anticipate genuine traffic conflicts in footage filmed from the driver's perspective, with separate groups tested at either 10 a.m. (lower sleepiness) or at 3 a.m. (higher sleepiness). We found a significant interaction between sleepiness and experience, indicating that the hazard perception skills of the more experienced drivers were relatively unaffected by mild increases in sleepiness while the inexperienced drivers were significantly slowed. The findings suggest that the disproportionate sleepiness-related accident involvement of young, inexperienced drivers could be partly due to a slowing of their ability to anticipate traffic hazards. 相似文献
996.
The resonant recognition model (RRM) is a physicomathematical approach used to analyze the interactions of a protein and its target, using digital signal processing methods. The RRM is based on the finding that there is a significant correlation between the spectra of numerical presentation of protein sequences and their biological activities. Initially, the electron-ion interaction potential was used to represent each amino acid in the protein sequences. In this paper, the dielectric constant (/spl epsiv/') and dielectric loss tangent (tan /spl delta/) parameters have been determined for their possible use in the RRM. These parameters are based on the values of capacitance and conductance obtained experimentally for 20 amino acid solutions using dielectric spectroscopy for the case of the real component of dielectric permittivity; the parameter used is the dielectric increment (/spl Delta//spl epsiv/'), the difference between dielectric constant of the amino acid solution and that of the solvent alone. The results of multiple cross-spectral analyses have shown that parameters analyzed generate in the consensus spectrum one dominant peak corresponding to the common biological activity of proteins studied, allowing the conclusion that these new parameters are suitable for use in the RRM approach. 相似文献
997.
Characterizing the nature of medium-range order (MRO) in liquids and disordered solids is important for understanding their structure and transport properties. However, accurately portraying MRO, as manifested by the first sharp diffraction peak (FSDP) in neutron and X-ray scattering measurements, has remained elusive for more than 80 years. Here, using X-ray diffraction of amorphous red phosphorus compressed to 6.30 GPa, supplemented with micro-Raman scattering studies, we build three-dimensional structural models consistent with the diffraction data. We discover that the pressure dependence of the FSDP intensity and line position can be quantitatively accounted for by a characteristic void distribution function, defined in terms of average void size, void spacing and void density. This work provides a template to unambiguously interpret atomic and void-space MRO across a broad range of technologically promising network-forming materials. 相似文献
998.
999.
Huang PY Kurasch S Srivastava A Skakalova V Kotakoski J Krasheninnikov AV Hovden R Mao Q Meyer JC Smet J Muller DA Kaiser U 《Nano letters》2012,12(2):1081-1086
Large-area graphene substrates provide a promising lab bench for synthesizing, manipulating, and characterizing low-dimensional materials, opening the door to high-resolution analyses of novel structures, such as two-dimensional (2D) glasses, that cannot be exfoliated and may not occur naturally. Here, we report the accidental discovery of a 2D silica glass supported on graphene. The 2D nature of this material enables the first atomic resolution transmission electron microscopy of a glass, producing images that strikingly resemble Zachariasen's original 1932 cartoon models of 2D continuous random network glasses. Atomic-resolution electron spectroscopy identifies the glass as SiO(2) formed from a bilayer of (SiO(4))(2-) tetrahedra and without detectable covalent bonding to the graphene. From these images, we directly obtain ring statistics and pair distribution functions that span short-, medium-, and long-range order. Ab initio calculations indicate that van der Waals interactions with graphene energetically stabilizes the 2D structure with respect to bulk SiO(2). These results demonstrate a new class of 2D glasses that can be applied in layered graphene devices and studied at the atomic scale. 相似文献
1000.
Chunlei Li Shaoguang Yang Rongkun Zheng Wenrong Yang Simon Ringer 《Materials Letters》2009,63(12):1016-1018
α-Al2O3 nanowires, with diameter around 10 nm, were synthesized in bulk quantity by heating the mixture of pure aluminum and graphite powders at 900 °C. Scarcity of oxygen is regarded as the reason for the growth of the small diameter α-Al2O3 nanowires at relatively low temperature. The product was characterized by field emission scanning electron microscopy, high-resolution transmission electron microscopy and photoluminescence. The Oxygen vacancies in the nanowires lead to the strong photoluminescence in the wavelength range of 400-700 nm with its peak at 527 nm. 相似文献